Charged particle system

Abstract

To provide a charged particle system capable of facilitating comparison between an actual pattern and an ideal pattern using not only two-dimensional CAD data but also three-dimensional CAD data. According to the present invention, using information about the angle of irradiation of a sample with a charged particle beam, a two-dimensional display of an ideal pattern (design data, such as CAD data, for example) is converted into a three-dimensional display, and the three-dimensional ideal pattern is displayed with an observation image. If the three-dimensional ideal pattern is superimposed on the observation image, comparison thereof can be easily carried out. Examples of the ideal pattern include a circuit pattern (CAD data) based on semiconductor design information, an exposure mask pattern based on an exposure mask used for exposure of a semiconductor wafer, and an exposure simulation pattern based on exposure simulation based on the exposure mask and an exposure condition can be used, and at least one of these patterns is displayed three-dimensionally.

1. A charged particle system, comprising:
 charged particle beam controlling means that controls a charged particle beam to scan a predetermined region of a sample with the charged particle beam; 
 charged particle applying means capable of irradiating said sample with said charged particle beam in an inclined direction; 
 observation image generating means that detects an electron emitted from a part of said sample irradiated with said charged particle beam when said sample is irradiated with the charged particle beam and generates an observation image of the region of said sample scanned with said charged particle beam based on the amount of electrons detected; and 
 image processing means that displays said observation image and an ideal pattern image on a display section, 
 said image processing means calculates an angle of display of said ideal pattern based on an inclination angle of said charged particle beam with respect to said sample, inclination-converts the shape of the ideal pattern, and displays the inclination-converted ideal pattern as a three-dimensional pattern on said display section. 
 
     
     
       2. The charged particle system according to  claim 1 , wherein said ideal pattern includes at least one of a circuit pattern based on semiconductor design information, an exposure mask pattern based on an exposure mask used in exposure of a semiconductor wafer, and an exposure simulation pattern based on exposure simulation based on the exposure mask and an exposure condition. 
     
     
       3. The charged particle system according to  claim 1 , wherein said image processing means displays said ideal pattern superimposed on said observation image on said display section. 
     
     
       4. The charged particle system according to  claim 1 , wherein said image processing means displays said observation image and said ideal pattern as a two-dimensional pattern that is not inclination-converted simultaneously with said inclination-converted ideal pattern on said display section. 
     
     
       5. The charged particle system according to  claim 1 , further comprising pattern matching means that carries out pattern matching between said ideal pattern and said observation image. 
     
     
       6. The charged particle system according to  claim 5 , wherein said image processing means has a function of said pattern matching means. 
     
     
       7. The charged particle system according to  claim 1 , further comprising pattern shifting means that enables manual alignment between said ideal pattern and said observation image. 
     
     
       8. The charged particle system according to  claim 1 , further comprising:
 inputting means that is used for inputting at least one of the order of display and the thickness of at least one of a plurality of layers forming the ideal pattern as the three-dimensional pattern; and 
 storing means that stores the input information. 
 
     
     
       9. The charged particle system according to  claim 8 , wherein said image processing means displays on said display section at least one of the order of display and the thickness of at least one of the plurality of layers forming said ideal pattern. 
     
     
       10. The charged particle system according to  claim 1 , wherein said image processing means carries out a reverse conversion of the ideal pattern as the three-dimensional pattern into the ideal pattern as the two-dimensional pattern based on the inclination angle of said sample and an instruction from an operator to display the ideal pattern of the two-dimensional pattern on the display section as said observation image. 
     
     
       11. The charged particle system according to  claim 1 , further comprising means of changing the focus and the scanning position of said charged particle beam controlling means based on positional information including the length, the width and the height of said ideal pattern.